
#ifndef __ui_gfx_jpeg_codec_h__
#define __ui_gfx_jpeg_codec_h__

#pragma once

#include <vector>

class SkBitmap;

namespace gfx
{

    // Interface for encoding/decoding JPEG data. This is a wrapper around libjpeg,
    // which has an inconvenient interface for callers. This is only used for UI
    // elements, WebKit has its own more complicated JPEG decoder which handles,
    // among other things, partially downloaded data.
    class JPEGCodec
    {
    public:
        enum ColorFormat
        {
            // 3 bytes per pixel (packed), in RGB order regardless of endianness.
            // This is the native JPEG format.
            FORMAT_RGB,

            // 4 bytes per pixel, in RGBA order in mem regardless of endianness.
            FORMAT_RGBA,

            // 4 bytes per pixel, in BGRA order in mem regardless of endianness.
            // This is the default Windows DIB order.
            FORMAT_BGRA,

            // 4 bytes per pixel, it can be either RGBA or BGRA. It depends on the bit
            // order in kARGB_8888_Config skia bitmap.
            FORMAT_SkBitmap
        };

        // Encodes the given raw 'input' data, with each pixel being represented as
        // given in 'format'. The encoded JPEG data will be written into the supplied
        // vector and true will be returned on success. On failure (false), the
        // contents of the output buffer are undefined.
        //
        // w, h: dimensions of the image
        // row_byte_width: the width in bytes of each row. This may be greater than
        //   w * bytes_per_pixel if there is extra padding at the end of each row
        //   (often, each row is padded to the next machine word).
        // quality: an integer in the range 0-100, where 100 is the highest quality.
        static bool Encode(const unsigned char* input, ColorFormat format,
            int w, int h, int row_byte_width,
            int quality, std::vector<unsigned char>* output);

        // Decodes the JPEG data contained in input of length input_size. The
        // decoded data will be placed in *output with the dimensions in *w and *h
        // on success (returns true). This data will be written in the'format'
        // format. On failure, the values of these output variables is undefined.
        static bool Decode(const unsigned char* input, size_t input_size,
            ColorFormat format, std::vector<unsigned char>* output,
            int* w, int* h);

        // Decodes the JPEG data contained in input of length input_size. If
        // successful, a SkBitmap is created and returned. It is up to the caller
        // to delete the returned bitmap.
        static SkBitmap* Decode(const unsigned char* input, size_t input_size);
    };

} //namespace gfx

#endif //__ui_gfx_jpeg_codec_h__